The Diels-Alder cycloadditions of the alpha-acetoxynitroso dienophile in water are reported. The rapid and high yielding synthesis of structurally diverse 3,6-dihydro-1,2-oxazines complements the straightforward elaboration of aminoalcohols obtained from the alpha-acetoxynitroso derivative in anhydrous medium. A rationale for this solvent-dependent product distribution is proposed.
Nitroso-Diels-Alder cycloaddition of various dienes combined with a straightforward sequence including N-O bond cleavage and oxidation reaction of the resulting (Z)-γ-aminoenone (or enal) leads to polysubstituted pyrrolic units.